Heat-treating apparatus



A. S. MACDONALD AND 'E. M. HUGGINS.

HEAT TREATING APPARATUS. APPLICATION FILED MAY I0, ms.

1 34,663. Patented Mar. 23, 1920.

3 SHEETSSHEET l- A TTOR/VEVS III A. S. MACDONALD AND E. M. HUGGINS.

HEAT TREATING APPARATUS. APPLICATION FILED MAY 10. mm.

Patented Mar. 23, 1920.

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HEAT TREATING APPARATUS. APPLICATION FILED MAY 10. I919.

Patented Mar. 23, 1920,

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UNITED STATES PATENT ornion.

ANGUS s. MACDONALDLOF GREAT NECK STATION, AND EDWARD OF NEW YORK, N, Y.

MELVILLE HUGGINS,

HEAT-TREATING; APPARATUS.

Specification of Letters Patent. Patented Mar. 23, 1920.

Application filed May 10, 1919. Serial No. 296,217.

To all whom it may concern:

ANGUS S. Mac- DONALD and EDWARD MELVILLE HUGGINS,

both citizens of the United States, res'id- 'ing at Great Neck Station, in the county of Nassau and State of New York, and New York city, in the county of New York and State of New York, respectively, have invented certain new and useful Improvements in Heat-Treating Apparatus, of which the following is a specification.

This invention relates to improvements in apparatus for the heat treating, or heat treating and tempering of metallic articles, and it has for one of its primary objects the provision of simple and improved mechanism whereby the treating or temper- I ing, or both, may be accomplished'economically and expeditiously, and with uniform results. Another object resides in the provision of improved apparatus of the character specified for heat treating strips, sheets, plates, and similar fabricated metallic members insuch manner as to prevent warping anddistortion thereof during both the heat treatment and tempering operations. Our invention also contemplates the provision of improved temperature indicating mechanism for translating the expansion or contraction of the articles undergoing treatment into terms of temperature readings, such indicating mechanism automatically accommodating itself to variations in the dimensions of the articles to be treated.

The foregoing, together with such other objects as may hereinafter appear, or are incident to our invention, we have obtained by means of apparatus which we haveillustrated in preferred form inthe accompanyon an enlarged scale of the indicating tomperature mechanism; Fig. 6 is a perspective of another detail of our improvement; Fig. 7 is afragmentary side elevation of a modification of our improvement; and Fig.

8 is a partial plan and sectional view of the mechanism shown in Fig. 7.

This invention is applicable in general to that type of heating apparatus shown in 'U. S. Letters Patent to Macdonald and gluggisns, Number 1,274,919, issued August The apparatus comprises a 'main' frame 7 preferably composed of T-rails with which are associated a back'plate 8 and a hinged door 9, both of which are composed of some suitable refractory insulating material such, for example, as asbestos fiber or the like. The T-rails extend downwardly into a tank or well 10 adapted to contain a quenching medium sifch, for example, as oil,-

and the back plate 8 and hinged door 9 are carried approximately from the level of the tank 10 to the top of the frame so that the upper part of the frame constitutes an inclosing box adapted to prevent radiation which would be particularly excessive where the article to be treated is a steel strip or plate. In the drawings, we have shown a steel sheet or strip 11 as'the articleunder goingheat treatment. This strip is suspended from an upper pair of jaws 12 and is alsohupported by a lower pair of jaws 13, such jaws also constitutin the terminals for the leads 14: and 15. ach jaw comprises a pair of plate-like members, one of which is provided with means for slidably engaging the T-rails, the other being clamped to said first member, with the strip 11 therebetween, by suitable fastening means such, for example, as the bolts 14 The plates comprising each pair of jaws conform to the shape of the article so as to prevent the article from becomlng transversely distorted or warped, and while we l1ave shown such jaws in the drawings in the form of plates, it will be readily understood that they may be shaped to suit any particular configuration of article. At various points intermediate the jaws 12 and 13, the article may be supported by clamps 15 which are adapted to slidingly embrace the T-rails and are constructed so as to engage the article throughout its width.

-These clamps, however, .haveli a relatively;- thin strip-engaging "surface, sq as to reduce- I the upper contact'or vision of a weight 22 .suspended mensions of the scale G.

ture scale. v

I will out from the principle that 'ature rises, and the lines I are the liability of cold spots. it will, of course,

be apparent that the aws 12 and 13 and 18 operated by 19 through the gearing 20. mounted on the bracket 21 seto one of the T-rails 7.

y means of e treadle mechanism indicated as a Whole hereinafter more particularly y suspending the article from ency ment during the heating and this advantageous result may be augmented by the profrom the lower contact 13. ounted in standards 23 carriedby the bracket 21 is a shaft-24, with which is associated a temperature dial F, the shaft 24 being driven from the shaft 18 of the drum 18 b Fig. 5). At the periphery, the dial F is provided with a linear scale G for indicatin lower contact 13 is normally held in th H the position indicated in Fig. 1 b

g an article having a length of 22 the length of the article being treated. The. b

dla'l isv also provided with radial 'lines or" markings H corresponding to the major di- The radial lines H the lines This scale may be readily worked the volume of a are intersected by I of a temperametallic object is a functionof the temperature. The article will expand as the temperobtained by pointing off on the radial line H the amount of expansion for every rise of 100 drawing the lines therethropgh.

ivoted 'to one of the T-rails 7 or some other suitable part of the apparatus, is an indicator arm 26 which is operated from the lower contact 13 and thegear segment 28,

when th arm 26 will point to zero temperature.

he mechanism E, by means of .which the lower contact is held in upperposition, will now be described, and it comprises a treadle 29'pivoted to one of the T-rails 7 a shaft 30 rot atably carried by such T-rail and having the treadle 29 by the link 33.

Normally, .the treadle 29'is spring held in upper position, in which position the arm 32 is free of-the contact 13 and will permit the contact 13 to sink freel When the treadle 29 is depressed the sha 30-is bring the'arm 32 into engagement with and maintain the contact 13in upper posilocked, which position of the dial y means of the gearing 25 (see t resistance to i th tion until a new in position and treadle.

The operation of the mechanism is as follows, assuming that the contact 13 is held in upper position by the treadle mechanism, as described :A steel sheet, plate or other article is clamped in the upper jaws and the hand-wheel 19 is rotated to lower the upper contact and the article until its lower end is in position to be .and clamped by e jaws or contact 13. Th mec article has been placed he operator releases the be correspondingly rotated until the radial line H, corresponding to the le'ngth'of the article, will be brought into or approximately into) the vertical position indicated in, Figs. 1 and -5. Thus, the will always correspond o the distance between the contacts. In Fig. 5 the radial line H, corresponding to ft, has been rought to a vertical position. The end cf. the pointer will follow this radial line H, the pointer is rotated about-its pivot polnt. by the sinking of the contact 13, through the medium of the-tack 27 and gear segment 28.

With the article thus switch 34 is closed and current, from suitable source of supply, passes through the article Whichbecomes heated by its internal e passage of the current therethrough. "As the article becomes heated; it expands and the lower contact sinks, causing the pointer (which is designed to greatly amplify themovement of the contact 13) to move upwardly following the radial line H and clearly indicate the temperature of the article as it crosses the spiral intersecting lines "I of the temperature scale. By following the movement of the pointer, the operator will thus be continuously' advised as to the temperature of the article 'and when this has reached the deoff the current.

positioned, the

and the clamps 15 will warping prevent and distortion not only during the fer.

temperature in different seasons of the year,

we prefer to form the pointer 26 and the l supported by drum 18, the shaft 18' 65 segment 28 separately, as shown, so that the position of the pointer can be readily adjusted to suit the atmospheric temperature. As one means for accomplishing this result, we have pivotally mounted the segment 28 on the pivot point 26 and provided such segment with an arcuate slot through which projects a bolt 36 carried on the pointer'26, and the gear segment and pointer are locked in adjusted position by means of the wing nut 37.

It will be seen from the foregoing that we haveprovided a simple means for indicating the temperature of the article being treated,

such means automatically accommodating itself to variations in length within the capacity of the apparatus. By the use of an electric current as the heating medium, the articles are heated substantially uniformly substantially throughout their length, and the temperature indicating mechanism makes it possible to obtain absolute uniformity in the'heat treatment of an'indefinite number of articles, thus securing uniformity in physical properties which is of great importance, particularly in the heat treatment of fabricated members adapted to be placed under considerable strains, such, for example, as aeroplane parts. Furthermore, the operator is materially assisted in obtaining uniform results because of the fact that during thetransformation periods, the pointer will temporarily pause or retrogress as the case may be. Thus, during the critical period in which the physical changes in the steel undergoing treatment take place, the pointer will pause in its movement.

It will, of course, 'be apparent that the linear and temperature scales may be altered or amplified to any degree that may be called for, depending upon thenicety of indication desired. It will also be apparent that considerable modification can be made from the particular form of apparatus shown, and it is to be further understood that the "apparatus may be utilized for carrying out a variety of heat treating operations. The dial may be graduated for any definite starting temperature.

In the modification we have shown. in

Figs. 7 and 8, the temperature indicating Y mechanism is much simplified. In this arrangement, as

the cable passmg' over the throughthe gearing 20. However, at the before, the upper contact is of which is driven inner end of the shaft 18' is a helical gear 40 engaging a helical gear 41 on a vertical shaft 42. Splined to the upper end of the shaft 42 is another helical. gear 43 engaging helical gear 44' keyed to the threaded shaft 45, mounted in a movable frame 46, such frame slidably engaging the T-rail 7, in the manner indicated in Fig. 8. The frame 46, which carries the gear 43, rests upon an abutment on the lower contact 13, and by virtue of its weight moves with such contact, the movement being permitted by virtue of the splined mounting of the gear 43 on the shaft 42.

A stationary bracket 47 .is bolted to the .rail 7 and the indicator arm 26 is pivoted to such bracket, as indicated at 48 in- Fig. 7 The indicator arm is provided with a slot 49 in which is slidably mounted theblock 50,

pivoted to a second block 51 which has threaded engagement with the threaded shaft and is slidably supported in the frame 46 by means of the rod 52'.

The dial F in this construction is stationary and is provided with a single temperature scale, andbecause of this fact, and also because the pivot point 48 is fixed, it will be apparent that some means must be rovided to compensate for variations in ength of the articles being treated'becaus'e the amount of expansion and contraction of such articles will be dependentupon their length; To state the matter in other words,

the dial F and the pivot point 48 are fixed factors, the length of the article is variable, and consequently, a variable factor must be employed to give the pointer 26 the properamount of travel corresponding to the length of the particular article being treated.

This condition has been met by means of the movable blocks and 51," such blocks imparting movement to the pointer 26 about its pivot point 48 because they in turn are movable with the frame 46. which, in turn, moves with the contact 13. The distance between pivot points 50' and 48 will determine the amplitude of the movement imparted to the pointer, and by virtue of the gearing employed, the distance between the twopivot points will always correspond to the length of the article, for the reason that'the amount of cable fed out from the drum 18 corresponds to the length of the article, and the turns imparted to the drum 18 are also imparted to shaft 45, and consequently, to blocks 51 and 50. If the article is short, points 48 and 50" will be close tomovement of the, pointer; if the article is long, the points will be farther apart, de-

gather increasing the amplitude of the I 53. Contact 13 will then have brought expand, means for transferring the article framenltto the position indicated in Fig. into the bath, and means for heating the in which. position pointer 26 registers zero article.

An apparatus for heat treating metallic 2. treated is then secured in the upper contact articles comprising in combination a bath, and the cable is, fed out until the lower end a frame extending into the bath, a plurality I of the article is brought into position vto be of clamping elements slidably carried in the the article expands as it becomes heated, articles comprising in combination a bath a engaged bythe lower contact 13. When this frame adapted to detachably receive the adjustment is effected, the blocks 51 and 50 article to be treated and support it with will be shiftedin position until the distance freedom to expand, means for heating the etweenpoints 50 and 48 also correspond article, and means for lowering the article to the length of the article. The tiyeadle is into the bath.

now released, the current turned on, and as 3. An apparatus for heat treating metallic imparting movement to the pointer 26 about a apted to receive the article to betreated,

o the amount of expansion of the artlcle in which the article to be treated is adapted being treated. When the pointer indicates to be heated, a plurality of clamping elea temperature which is suitable for the parments adapted to embrace the article at a ticular heat'treating operation being carried plurality of points intermediate its' ends, on, as above pointed out, current is'turned said clamping elements being slidably off, and the article is submerged in the bath guided on said frame, and means for heatfor quenching or removed from themachine, ing the article. if raised only, to the drawing temperature. 5. An apparatus for heat treating metallic As before, the pointer 26 is made 'adjustarticles comprising in combination a frame 95,

. able so that itmay be accommodated to atadapted to receive articles of varying mospheric conditions in order to obtain aclengths, means for heating the article, means curacy. n for supporting the article at an end thereof When the parts are beinglowered into with freedom to expand, and indicating the bath, frame 46 and its associated parts mechanism for translating the expansion of of the frame is limited. Stop 5 however, ing itself to variations in the length of the d movement imparted to the frame 46 when 6. apparatus for heat treating metallic the article expands or contracts. articles comprising in combination a frame desired the temperature indicating adapted to receive articles of varying mechanism may be-self recording, for which lengths, means for supporting the article at purpose a--- pencil 5-6 or other marking de-, each end thereof with freedom to expand,

e vice ma be mounted in the end of the and indicatin mechanism translatin the y g g pointer and a loose temperature card placed expansion of the article into terms of temon the pins 55 (see Fig, 7). A record may perature reading, said means automatically thus be kept for every piece of material accommodating itself to the distance betreated. Furthermore, the bar or rod 52 tween the saidsupporting means. may be rovided with a scale, as illustrated An apparatus for heat treating metallic in Fig. for indicating the length of each articles comprising in combination a frame piece treated.

It is to be noted that the manner of suslengths, a pair of contacts adapted to suppending the sheet from the upper contact port the article undergoing treatment at the under the weight of thelower contact places endsthereof with freedom to expand, and

pansion of the article into terms of temperarticles comprising in combination a bath, 8. An apparatus for heat treatingmetallic a supporting frame extending thereinto, articles comprising in combination 'a suitable means for movably supporting the article rame, a pair of article supportinglimem- 65 to be treated in said frame with freedom to bers adapted to support the article in the frame, both of said membersbeing movable, a pointer operated by one of said members and a temperature indicating dial cooperating with said pointer andoperatively associated with the other of said members.

9. An apparatus for heat treating metallic articles comprising in" combination a suitable frame, a pair of members adapted to sup port the article to be treated in the frame,

said members being movable, a pointer opj lic articles comprising in combination a suitable frame, means for supporting the article to be treated movably mounted in said frame, a cable from which said means is suspended, a drum on which the cable is wound, a dial having a linear scale adapted to be operated from said drum, a second means for supporting the article in the f'rame, and a pointer operated by said second means and cooperating with said dial, said dial also. having a temperature scale.

11. An apparatus for heat treating metallic articles comprising in combination a suitable frame, an article supporting member slidably mounted in said frame and from which the article is suspended, a second article supporting member adapted to support the article at the lower end thereof, a pointer operated by said second member, means for releasably fixing the position of said second member, a dial with which said pointer cooperates having a temperature scale and having a linear scale, and an operating connection between said first article supporting member and said dial.

12. An apparatus for heat treating metallic articles comprising in combination means for supporting the article at an end thereof with freedom to expand, and indicating mechanism fortranslating the expansion of the article into terms of temperature reading, such means being operable'by the article as it expands.

I 13. An apparatus for heat treating metallic articles comprising in combination a suitable frame, a pair of article engaging members adapted to support the article in the frame, one of said members being movable relative to the other, and indicating mechanism operated by said movable memher for translating the expansion of the article into terms of temperature reading.

14. An apparatus for heat treating metallic articles comprising in combination means for supporting the article, said means being adjustable to suit the length of the article, and indicating mechanism operated from said supporting means and having length of the article to be treated and in tersecting temperature graduations translating the expansion of the article into terms of'temperature reading, and an indicator member cooperating with said dial and operable by the article.

17. An apparatus for heat treating metallic articles comprising in combination a 7 frame in which the article is adapted to be suspended, an upper clamping element adapted to detachably engage the upper end of the article, a lower clamping element adapted to detachably engage the lower end of the article, both of said clampingelements being slidably mounted on the frame, and means for fixing the position of one of said clamping elements while the other clamping element is being adjusted to the length of the particular article undergoing treatment.

18. In apparatus of the character described, the combination of two relatively movable article engaging members, a graduated dial, a pointer actuated by the expansion of the article having a fixed center or pivot, and mechanism for modifying the amplitude of movementof the points in accordance with the distance between the said members.

19. Ari-apparatus for heat treating metallic articles comprising in combination a bath, a frame extending into the bath, a plurality of clamping elements, slidably carried on the frame and adapted to detachably receive'the article to be treated, means for heating the article and means for transferring the article into the bath while being held by the clamps.

20. In apparatus for heat treating metallic articles, the combination of means for supporting the article, and a self recording mechanism automatically translating and recording the changes in physical dimensions of the article undergoing treatment into terms of temperature.

21.- In heat treating apparatus the combination of a pair of article supporting members relatively movable, a temperature indicating mechanism operated by change in physical dimensions of the article being treated, and means associated indicating the length of th n heat treatin bination of a palr of "5 members members to articles e article or accommodatin of different lengt therewith for g apparatus the comrelatively movable adapted to receive the article to be treated, means if g said and Intestimony whereof we hereunto sign our names.

S. MACDONALD.

ANGUS E. MELVILLE HUGGIN S. 

